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 ###Instrução: Qual é o Userpics Free, quando o Registro está Aberto, quando o Custo Anual para Conta Paga é "desconhecido" e quando o Nome é Kraslan?
 ###Tabelas: CREATE TABLE personnel_and_sponsorship (personnel_and_sponsorship_id AUTO_INCREMENT PRIMARY KEY, Team VARCHAR, Chairman VARCHAR, Head Coach VARCHAR, Captain VARCHAR, Kitmaker VARCHAR, Shirt sponsor VARCHAR) CREATE TABLE energy-efficient_'e'_series (energy-efficient_'e'_series_id AUTO_INCREMENT PRIMARY KEY, Model Number VARCHAR, Stepping VARCHAR, Frequency VARCHAR, L2 Cache VARCHAR, Multi 1 VARCHAR, V Core VARCHAR, Socket VARCHAR, Release Date VARCHAR, Part Number(s) VARCHAR) CREATE TABLE full_members (full_members_id AUTO_INCREMENT PRIMARY KEY, Institution VARCHAR, Location (Population) VARCHAR, Founded INT, Type VARCHAR, Enrollment INT, Nickname (Colors) VARCHAR, Football? VARCHAR) CREATE TABLE us_ratings (us_ratings_id AUTO_INCREMENT PRIMARY KEY, # INT, Airdate VARCHAR, Episode VARCHAR, Rating VARCHAR, Share INT, Rating/Share (18–49) VARCHAR, Viewers (millions) VARCHAR, Rank (Timeslot) INT, Rank (Night) INT) CREATE TABLE general_information__&__feature_comparison (general_information__&__feature_comparison_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Year Began VARCHAR, s Registered user VARCHAR, Updated in past 30 days VARCHAR, Registration VARCHAR, Ability to syndicate off-site feeds VARCHAR, Userpics Free VARCHAR, Userpics Paid VARCHAR, Monthly Cost for Paid Account VARCHAR, Yearly Cost for Paid Account VARCHAR, Permanent Account VARCHAR)  
SELECT Userpics Free FROM general_information__&__feature_comparison WHERE Registration = open AND Yearly Cost for Paid Account = unknown AND Name = kraslan